The Burrows-Wheeler Transform is a building block for many text compression applications and self-index data structures. It reorders the letters of a text T to obtain a new text bwt(T ) which can be better compressed. This forward transform has been intensively studied over the years, but a major problem still remains: bwt(T ) has to be entirely recomputed whenever T is modified. In this articl...

We continue here the analysis of the previous paper of the Wheeler-DeWitt constraint operator for four-dimensional, Lorentzian, non-perturbative, canonical vacuum quantum gravity in the continuum. In this paper we derive the complete kernel, as well as a physical inner product on it, for a non-symmetric version of the Wheeler-DeWitt operator. We then define a symmetric version of the Wheeler-De...

CONTEXT Authorizing powered two-wheeler drivers to drive in lanes reserved to buses is a measure that is sometimes mentioned to improve mobility conditions for these users. But what effect would this measure have on the safety of these users and on the safety of the other users with whom they share the traffic space? OBJECTIVE The objective of this study is to contribute elements to help answ...

After a general description of the Burrows Wheeler Transform and a brief survey of recent work on processing its output, the paper examines the coding of the zero-runs from the MTF recoding stage, an aspect with little prior treatment. It is concluded that the original scheme proposed by Wheeler is extremely efficient and unlikely to be much improved. The paper then proposes some new interpreta...

Wormhole boundary conditions for the Wheeler-DeWitt equation can be derived from the path integral formulation. It is proposed that the wormhole wave function must be square integrable in the maximal analytic extension of minisuperspace. Quantum wormholes can be invested with a Hilbert-space structure, the inner product being naturally induced by the minisuperspace metric, in which the Wheeler-...

ÐA very interesting recent development in data compression is the Burrows-Wheeler Transformation [1]. The idea is to permute the input sequence in such a way that characters with a similar context are grouped together. We provide a thorough analysis of the Burrows-Wheeler Transformation from an information theoretic point of view. Based on this analysis, the main part of the paper systematicall...

The Wheeler-DeWitt equation in quantum gravity is timeless in character. In order to discuss quantum to classical transition of the universe, one uses a time prescription in quantum gravity to obtain a time contained description starting from Wheeler-DeWitt equation and WKB ansatz for the WD wavefunction. The approach has some drawbacks. In this work, we obtain the time-contained Schroedinger-W...

Die verlustfreie Datenkompression auf Grundlage der Burrows-Wheeler-Transformation ist in den letzten Jahren aufgrund Ihrer Effizienz und bemerkenswerten Eleganz auf ein großes Interesse gestoßen. Selbst einfache Implementierungen erreichen Geschwindigkeiten und Kompressionsraten von bekannten kommerziellen Pr ogrammen. Die Burrows-Wheeler-Transformation basiert auf einer Permutation von Eingab...

We study the half advanced and half retarded Wheeler Green function and its relation to Feynman propagators. First for massless equation. Then, for Klein-Gordon equations with arbitrary mass parameters ; real, imaginary or complex. In all cases the Wheeler propagator lacks an on-shell free propagation. The Wheeler function has support inside the light-cone (whatever the mass). The associated va...